This invention relates generally to heat controls and in particular to a method of actuating means for detecting radiant heat and a system in which the detecting means is utilized.
In the past, various types of detectors for radiant heat have been employed for controlling electrical circuits to effect, under preselected conditions, a flow of combustible gas and the ignition thereof so as to regulate the temperature of an appliance or apparatus, such as a gas dryer of the like for instance. In a past method for actuating such a detector, a generally U-shaped bimetal strip was subjected to radiant heat for completing an electrical circuit through the detector, but one of the disadvantageous or undesirable features thereof is believed to be that the bimetal acted generally as a long spring having a relatively high mass at the contact end thereof which was subject to low frequency vibrations. Another disadvantageous or undesirable feature of a past method for actuating such a detector is believed to be that during a change of ambient temperature, the detector portion of the bimetal deflected considerably necessitating the compensating portion of the bimetal to deflect the same and exact amount in opposition. Still another disadvantageous or undesirable feature of a past method for actuating such a detector is believed to be that the current flow in the electrical circuit was through the bimetal strip. Such current flow through the bimetal not only dictated the size thereof but also affected its operating characteristics by adding heat thereto. In other such past methods of actuating such detectors, the one of the thermo-responsive elements for controlling an electrical circuit through the detector is believed to be completely encapsulated by another thermal responsive element, and a disadvantageous or undesirable feature of this past detector is believed to be that the response time was too slow due to the complete shielding.